TY  - JOUR
A1  - Peng, Xingzhou
A1  - Behl, Marc
A1  - Zhang, Pengfei
A1  - Mazurek-Budzynska, Magdalena
A1  - Feng, Yakai
A1  - Lendlein, Andreas
T1  - Synthesis of Well-Defined Dihydroxy Telechelics by (Co)polymerization of Morpholine-2,5-Diones Catalyzed by Sn(IV) Alkoxide
JF  - Macromolecular bioscience
N2  - Well-defined dihydroxy telechelic oligodepsipeptides (oDPs), which have a high application potential as building blocks for scaffold materials for tissue engineering applications or particulate carrier systems for drug delivery applications are synthesized by ring-opening polymerization (ROP) of morpholine-2,5-diones (MDs) catalyzed by 1,1,6,6-tetra-n-butyl-1,6-distanna-2,5,7,10-tetraoxacyclodecane (Sn(IV) alkoxide). In contrast to ROP catalyzed by Sn(Oct)(2), the usage of Sn(IV) alkoxide leads to oDPs, with less side products and well-defined end groups, which is crucial for potential pharmaceutical applications. A slightly faster reaction of the ROP catalyzed by Sn(IV) alkoxide compared to the ROP initiated by Sn(Oct)(2)/EG is found. Copolymerization of different MDs resulted in amorphous copolymers with T(g)s between 44 and 54 degrees C depending on the molar comonomer ratios in the range from 25% to 75%. Based on the well-defined telechelic character of the Sn(IV) alkoxide synthesized oDPs as determined by matrix-assisted laser desorption/ionization time of flight measurements, they resemble interesting building blocks for subsequent postfunctionalization or multifunctional materials based on multiblock copolymer systems whereas the amorphous oDP-based copolymers are interesting building blocks for matrices of drug delivery systems.
KW  - oligodepsipeptides
KW  - ring-opening polymerization
KW  - Sn(IV) alkoxide
KW  - telechelics
KW  - tin(II) 2-ethylhexanoate
Y1  - 2018
U6  - https://doi.org/10.1002/mabi.201800257
SN  - 1616-5187
SN  - 1616-5195
VL  - 18
IS  - 12
PB  - Wiley-VCH
CY  - Weinheim
ER  - 
TY  - JOUR
A1  - Behrendt, Felix Nicolas
A1  - Schlaad, Helmut
T1  - Entropy-Driven Ring-Opening Disulfide Metathesis Polymerization for the Synthesis of Functional Poly(disulfide)s
JF  - Macromolecular rapid communications
N2  - Metal-free entropy-driven disulfide metathesis polymerization of unsaturated L-cystine based macrocycles produces high-molar-mass heterofunctional poly(disulfide)s, i.e., poly(ester-disulfide-alkene) and poly(amide-disulfide-alkene); M-w(app) = 44-60 kDa, (sic) > 1.7. The polymerization is fast and reaches equilibrium within 1-5 minutes (monomer conversion 70-90%) in polar aprotic solvents such as N,N-dimethylacetamide, dimethylsulfoxide, or y-valerolactone. Thiol-terminated polymers are stable in bulk or when dissolved in weakly polar solvents, but rapidly depolymerize in dilute polar solution.
KW  - disulfide
KW  - macrocycles
KW  - metathesis
KW  - ring-opening polymerization
Y1  - 2018
U6  - https://doi.org/10.1002/marc.201700735
SN  - 1022-1336
SN  - 1521-3927
VL  - 39
IS  - 6
PB  - Wiley-VCH
CY  - Weinheim
ER  -